ASUS ZenWiFi XT8

Asus XT12s (really hard to find now but XT8/9 are easy to find and have really solid performance for the price).

If it were me, I'd return the AX3000 and buy a 2 or 3 pack of XT-8s (or possibly their updated version they have in the same form factor). I've had no problem, having installed 8 (2 routers, 6 AP's) of them.

ASUS XT8 is a great WiFi 6 mesh system that I recommend and use myself. It works well in wireless or wired backhaul.

I have an ASUS XT8 mesh system. Used it with wireless backhaul for over 4 years. In the last few months switched to Ethernet backhaul (wired) when I installed MoCA adapters... The mesh system has worked well via both backhaul types.

When i used 3 asus xt8's in a three story house my router connected to my ONT was on the middle floor. I didn't see much difference in speed. If it was a 2 hoop situation I can't really be sure, but I wouldn't think it would be that major because of the tri band.

I've been using an ASUS XT8 (WiFi 6) mesh system for 4.5 years and it's been great the last 4 years. First half year there were firmware issues, but ASUS eventually fixed them.

I have an ASUS XT8 AiMesh system (also tri band, but for both the router and mesh node) and it works very well via wired or wireless backhaul.

I have had an Asus XT8 system (WiFi 6) for over 4 years and it works well.

Compare that to an ASUS XT8 tri-band mesh system which I have now ... In the same room as as the router i get 400mbps. Downstairs, separated by one floor in the main room, I get 400mbps. ... With the ASUS XT8 mesh I get almost 100% speed everywhere.